An information processing system acquires positional information of a vehicle, acquires positional information of a terminal device, estimates current transportation means of a user based on the positional information of the terminal device, decides information relating to a first route, along which the user moves to the vehicle, based on the positional information of the terminal device, the estimated current transportation means of the user, and the positional information of the vehicle, decides information relating to a second route, along which the user who has moved to the vehicle moves to a destination using the vehicle, based on a first predicted arrival time, the positional information of the vehicle, and positional information of the destination, and outputs first guide information for prompting the user to start moving along the first route in a form of a video or a sound.